NOTES AND ABSTRACTS. 



779 



Crown Gall of the Grape, Field Studies of. By George G. 

 Hedgcock {U.S.A. Dep. Agr., Bur. of PL Ind., Bull.- 183). —This 

 disease which attacks both root and canes of the grape vine is due to a 

 bacterium, Bacillus tumaefaciens. The same produces galls also on the 

 tomato, tobacco, potato, sugar beet, hop, peach, cherry, &c. Some 

 species of Vitis are rnuch more resistant to the disease than Vitis 

 vinifera, the chief being V. rupestris, V. vulpina (v/hich are almost 

 immune), some varieties of Vitis aestivalis, V. Lahrusca, &c. American 

 varieties of grape vine are not nearly so susceptible as the European, and 

 vines which are very sensitive to frost are much more prone to the 

 disease. The bacterium is a wound parasite, and the galls generally 

 develop at the junction of stock on scion, injure the root, and spread up 

 the stem and become confluent. Apples and pears when artificially 

 inoculated with the bacterium gave negative results. The disease may 

 be spread by irrigation (especially surface irrigation), insects, birds, the 

 pruning knife, &c. Spraying with fungicides and the cutting away of 

 galls from the root and canes proved absolutely useless, and the writer 

 recommends burning the diseased vines and replanting with resistant 

 varieties as the only remedy. A good list of disease-resistant varieties is 

 given.— D. M. C. 



Cycnoches maculatum. By E. B. Behnick {Orchis, vol. iv, pt. vii. 

 pp. 104, 105; 1 plate). — Male and female flowers seldom appear on 

 the same plant. The flowers are pale green splashed with pale brown 

 spots.— E. W. 



Cymbidium insig-ne {Bot. Mag. tab. 8312).~Nat. ord. 

 Orchidaceae ; tribe Vandeae. Annam. Herb; leaves linear oblong, 

 3^ feet long; scapes 4 feet long; racemes, many-flowered; perianth, 

 spreading, 4 inches across, pale rose; lip with purple blotches. — G. H. 



Cypripedium, Fertilization of. By 0. N. Witt {Orchis, vol iv. 

 pt. vi. pp. 87-93 ; 3 plates). — The natural method of pollination 

 of Cypripedium is described. — S. E. W. 



Cyrtopodium punetatum. By 0. N. Witt {Orchis, vol. iv. 

 pt. iv. p. 57 ; 1 plate). — An illustration of this orchid in flower. 



S. E. W. 



Cytisus Dallimorei {Garden, June 11, 1910, p. 291; fig.).— The 

 plant was obtained as a cross from C. scoparius with the pollen of 

 G. albus. Two plants grew from this cross, the one yellow, the other 

 the subject of this note. It has rosy purple wing petals, and almost 

 crimson flowers half as long again as albus. It is interesting as being 

 an artificial cross, for probably all the other hybrid brooms have 

 originated as natural hybrids. — H. R. D. 



Daffodil, An Alkaloid from the Bulb of. By Arthur James 

 Ewins {Jour. Ghem. Soc. vol. xcvii. Dec. 1910, pp. 2406-2409).— 

 From time to time one finds or hears somewhat vague references to 



